feat(forum): add complete forum workflows

inc/modules/user-parts/template-registry.php

@@ -43,6 +43,12 @@ $_jio_special_templates = [
         'title'    => '发布文章',
         'fallback' => '/submit/',
     ],
+    'forums' => [
+        'file'     => 'templates/pages/page-forums.php',
+        'slug'     => 'forums',
+        'title'    => '论坛',
+        'fallback' => '/forums/',
+    ],
 ];
 
 /** @var array 缓存 key=模板文件路径 => value=WP_Post|null */